The MP/M experiment: MP/M 2.1 in action with 4 concurrent terminals/users

I was curios to see MP/M in action with 4 concurrent terminals. So I made all the needed HW.
The main board is a custom FPGA board I made to play with Multicomp VHDL implementations.
In this case I used a Z80 Multicomp with 4 serial ports.
All the HW is Open Source and all the documentation can be found online.